Hitherto, extraction and separation methods for extracting and separating a specific component from a raw material fluid have been known. For example, Patent Document 1 as described below discloses an example of such extraction and separation methods.
In Patent Document 1 as described below, an apparatus including a flow passage structure body in the interior of which a multitude of flow passages are provided is used for extracting and separating a specific component (extract) from a raw material fluid (fluid subject to extraction). Through each flow passage in the flow passage structure body, the raw material fluid and an extracting agent are allowed to flow while being in contact with each other, and during a flowing process thereof, the specific component is extracted from the raw material fluid to the extracting agent. A separation header is attached to an outer surface of the flow passage structure body. Outlet ports of upstream flow passages and inlet ports of downstream flow passages that are provided in the flow passage structure body communicate with an interior space of the separation header. A mixed fluid of the raw material fluid and the extracting agent that has flown through the upstream flow passages is discharged from the outlet ports of these flow passages to the interior space of the separation header. The mixed fluid that has been discharged to the interior space of the separation header is separated in the interior space due to a specific gravity difference into the raw material fluid and the extracting agent. The separated raw material fluid is fed into the downstream flow passages, and extraction of the specific component is further performed.
In the extraction and separation method disclosed in Patent Document 1 as described above, the mixed fluid discharged to the interior space of the separation header is thoroughly separated into the raw material fluid and the extracting agent. Consequently, a retention time of the mixed fluid in the separation header increases, and as a result, a treatment time required for extraction and separation increases. Moreover, the separation header is required to include a large-volume interior space that allows the mixed fluid to remain until the mixed fluid is thoroughly separated into the raw material fluid and the extracting agent. Consequently, the separation header is enlarged, and accordingly the whole body of a separation device is enlarged.